The resonant Auger electron spectrum of core-excited ethylene: A combined experimental and theoretical investigation

We present measurements and calculations of the electronic decay of core-ex cited states in gas-phase ethylene. We have studied the decay of C 1s --> p i* core-to-valence resonances and the decay of the 1s --> 3s, 1s --> 3p, an d 1s --> 4p Rydberg states. In addition, ab initio calculations are present ed for the final states from the decay of the 1s --> pi* resonantly-excited state. The final states are calculated using configuration interaction wav e functions for the intermediate (core-excited) state, and for the final st ate. The calculated spectrum compares well with the experimental spectrum a nd all final states may be identified. The method used for the calculation therefore seems very promising for other alkene molecules. (C) 1999 Elsevie r Science B.V. All rights reserved.